Thirteen healthy male volunteers ingested a single 0.25 mg dose of the thienodiazepine
hypnotic,
brotizolam, on two occasions: once with a typical social cocktail (containing 60 ml of vodka), and in a second trial with an '
ethanol-placebo' cocktail.
Brotizolam kinetics were determined from multiple plasma concentrations measured during the 24 h after dosage. Coadministration of
brotizolam with
ethanol, as opposed to the placebo cocktail, slightly imparied
brotizolam clearance (1.85 vs 2.19 ml min-1 kg-1 P less than 0.005), increased peak plasma concentrations (5.3 vs 4.3 ng ml-1, P less than 0.05), and prolonged elimination half-life (5.2 vs 4.4 h, P less than 0.05). There was evidence of impairment of performance, although not statistically significant, for the first 4-6 h after
brotizolam dosage in the reaction time test, the digit-symbol substitution test, and a tracking task. None of these was enhanced by
ethanol. In both trials,
brotizolam produced significant increases in self-rated perceptions of sedation,
fatigue, feeling 'spaced-out', and thinking slowed down. These effects were more intense during the
brotizolam-
ethanol as compared to
brotizolam-placebo. In both trials, recovery was essentially complete by 6-8 h after dosage. Coadministration of
brotizolam with
ethanol produces a small but significant impairment of
brotizolam clearance.
Brotizolam produced self-rated perceptions of sedation and
fatigue during 4-6 h after dosage, but objective impairment of psychomotor performance was minimal. Subjective perceptions of sedation were enhanced by
ethanol coadministration, but the effects on psychomotor performance were not.